1. Field of the Invention
The present invention relates to a placement device.
2. Description of the Related Art
In a disposable worn article such as a paper diaper, an elastic member is placed at a predetermined position for forming gathers (e.g., Japanese Laid-Open Patent Publication No. 9-70412). A gather control device described in this publication includes a pair of nip rolls for sandwiching an elastic member between two webs, and an aperture section for guiding the elastic member between the webs.
The device places the elastic member in a predetermined pattern on the web by moving the aperture section. The line along which the elastic member is placed varies for different sizes and designs of articles. If, for example, the position of the elastic member placed on the web along leg portions is shifted from the position of leg holes made in the web, a good product cannot be produced. Therefore, it is important to accurately form the line at a predetermined position.
However, the publication mentioned above fails to disclose a method for controlling the gather control device and other devices in phase with one another.